Shrub Composition Research Articles

Зеленые насаждения общественных пространств населенных пунктов Пермского края

Green spaces play a very important role in the structure of public landscaping facilities (parks, gardens, squares, boulevards), as they occupy more than 60% of the total area of the facilities and form the basis of the spatial structure of the territory. Sanitary and hygienic conditions, decorative planning solutions and the comfort of human stay in green spaces depend on the sanitary condition, aesthetic appearance, resistance to natural, climatic and environmental conditions of green spaces and on the spatial structure of the landscaping objects themselves. The most important issue for the Perm Region is the restoration and reconstruction of public spaces, including public landscaping facilities in various localities. Currently, as part of the implementation of the federal project "Comfortable Urban Environment", public landscaping facilities are being restored not only in large cities, but in small towns and other settlements of the Perm Territory. But in most cases, these public spaces are degraded to one degree or another, including in terms of landscaping. Currently, a significant part of the plantings in landscaped public areas requires the implementation of various forms of restoration to improve the aesthetic appearance and environmental conditions of the space itself. Taking timely measures will increase the longevity of the plantings and the attractiveness of the facility. This paper provides an analysis of the state of green spaces in public spaces using the example of a large city – Perm, a small one – Krasnovishersk and a settlement - Yugo-Kamsky settlement of the Perm Territory. In the course of the research, the species composition and number of trees and shrubs, the density of plantings, the sanitary condition and types of damage often encountered, the spatial structures of landscaping objects were determined and recommendations were given to improve the condition of green spaces. Keywords: SQUARE, PARK, SPECIES COMPOSITION, SANITARY CONDITION, TYPES OF DAMAGE, SPATIAL STRUCTURE, DENSITY OF PLANTINGS

High fire frequency in California chaparral reduces postfire shrub regeneration and native plant diversity

AbstractFire is crucial for maintaining species diversity and resilience in fire‐adapted shrublands of the world's Mediterranean climate zones (MCZs), which include the chaparral shrublands of the North American MCZ. Chaparral is adapted to high‐intensity burning, with relatively long intervals between fires (30–100 years) typifying undegraded conditions. Modern fire frequencies are much higher in chaparral, driven largely by high densities of human ignitions and coincidence between ignitions and severe weather conditions. This change in the fire regime has major implications for biodiversity, leading to exotic invasion, decreased ecosystem services, and potential type conversion of shrubland to grassland dominated by exotic species. We studied the impact of increased fire frequencies on the composition and abundance of herbaceous and woody species in the Interior Coast Range of northern California. Our study area is one of the most frequently burned areas in California, which allowed us to investigate higher fire frequencies than previously published in the scientific literature for California. We surveyed fifty‐four 250‐m2 plots to assess changes in plant community composition and postfire regeneration of chaparral shrubs across a wide range of fire frequencies, including plots that have burned up to six times in the past 30 years. Our findings reveal that short‐interval fires significantly reduced postfire native woody regeneration, with obligate seeding species experiencing a 99% reduction and facultative species showing an 83% reduction in regeneration in the most frequently burned plots. Moreover, the overall marginal effect of one additional fire since 1985 decreased the proportion of native species cover by 12% and both richness and Shannon diversity by 4%. Consequently, areas with higher fire recurrence supported a more structurally and botanically homogeneous landscape dominated by a homogeneous group of non‐native species.

Local extirpation of woody species in Colophospermum mopane woodland under chronic utilisation by elephants

AbstractThe hypothesis that certain woody species may be prone to local extirpation under chronic elephant utilisation was examined for Colophospermum mopane open woodland, for an area within the foraging range of elephants from permanent water. Elephant density increased from nearly absent in the 1970s to >3 elephants km−2, with 0.62 adult bulls km−2, by 2022. Study components of vegetation impact included a long‐term elephant exclosure, a fence‐line contrast with an adjacent communal area, comparison with an adjacent wildlife reserve carrying a fifth of the elephant density and the use of historical studies of the vegetation. A history of elephant utilisation resulted in woodland becoming hedged through pollarding of tree stems by elephants. Impacted woodland was characterised by a slightly lower tree density, reduced average height of trees, altered shrub composition and lower species richness. The dominant C. mopane and sub‐dominant species had persisted. However, about 14 species were potentially trending towards local extirpation on account of very high levels of adult mortality, but had persisted because of a low level of seedling recruitment. Fleshy fruits were a shared attribute among most extirpation‐trending species, which, together with a reduction in woody species richness that affects browsers, has ramifications for trophic flows.

The impact of sheep grazing on shrub communities at the Afrikaner and Hereford grazing trials at Grootfontein in the Eastern Upper Karoo

In the Nama-Karoo, grazing by livestock is an important driver of Karoo shrub composition. Many different breeds of livestock are farmed in the Nama-Karoo, and the stocking rate varies greatly over the region. In this study we examine how grazing by dorper and merino sheep applied at three stocking rates affected two Karoo shrublands on a long-term grazing trial at Grootfontein in the eastern Karoo. The effects of grazing treatment on shrub communities at two sites of the Afrikaner-Hereford grazing trial differed greatly and were measurable after ten years of rest. At the sandier, grassier Afrikaner site, heavy grazing by dorper sheep had a significant effect on shrub composition, density and cover, whereas the effect of grazing treatment was less pronounced at the Hereford site. Lenient grazing by merino sheep resulted in a vastly different community compared to all other grazing treatments. Individual Karoo shrub species responded differently to grazing treatment. Overall shrub recruitment has faltered for all but three species, and populations were dominated by intermediate-sized and large individuals. Results indicate that grazing management, animal type and stocking rate are important determinants of Nama-Karoo rangeland composition and structure with evidence of a legacy effect longer than ten years.

Temporal variation in nutritive value of forage in kermes oak shrublands

This study was carried out to determine the seasonal floristic composition of grasses, forbs, and shrubs in a kermes oak (Quercus coccifera L.) shrubland in Chalkidiki, Greece, to estimate their nutritive value and to relate it to the nutritional requirements of small ruminants. All the herbaceous and woody species that were present in the study area were identified and collected at the beginning of each season. The samples were categorized into grasses, forbs, and shrubs. Dry matter (DM), ash, ether extract (EE), neutral detergent fiber assayed with heat stable amylase (aNDF), crude protein (CP), in vitro dry matter digestibility (IVDMD), calcium (Ca), and phosphorus (P) contents were determined. Forty-three plant taxa were identified (30 forbs, 7 grasses, and 6 shrubs). Forbs had higher mean values of ash (94.7 g/kg DM), CP (120.9 g/kg DM), Ca (16.9 g/kg DM), P (1.2 g/kg DM), and IVDMD (590.5 g/kg DM) compared to grasses (72.5 g/kg DM, 86.5 g/kg DM, 3.9 g/kg DM, 0.9 kg-1 DM, and 517.8 g/kg DM), and shrubs (44.5 g/kg DM, 79.9 g/kg DM, 11.0 g/kg DM, 0.7 g/kg DM, and 494.7 g/kg DM), respectively. Cool-season grasses can offer sufficient nutrients to grazing animals during autumn and winter, while shrubs support them during spring and winter.

Distribution and Conservation Status of Plants’ species in the Botanical Garden and Arboretum domiciled in University of Uyo, Nigeria

This research assessed the plant species composition, distribution and International Union for the Conservation of Nature (IUCN) conservation status of plants in University of Uyo botanical garden and arboretum using systematic sampling technique. The species were sampled in 10 x 10 m quadrats spaced at least regular intervals of 20 m from each quadrat. Thirty-one and thirty-eight species were encountered in the arboretum and botanic garden respectively. In terms of the frequency, Chromolaena odorata and Nauclea diderichii had the highest values (75%), while Acanthus montanus, Anthocleista djalonensis, Anthonotha macrophylla, Baphia nitida, Barteria nigritiana, Carpolobia lutea, Ceiba pentandra, Cnestis ferruginea, Entandrophragma utile, Hura crepitans, Lonchocarpus griffoneonus, Rauvolfia vomitoria, Senna siamea, Tamarindus indica, Tectona grandis and Treculia africana had the least frequency (25% each). For the density, Nauclea diderichii had the value of 250±15.30 st/ha. In the botanic garden, Ageratum houstonianum, Alchornea cordifolia, Chromolaena ordorata and Croton hirtus had the highest frequency (100%) while Allamanda cathartica, Asystasia gangetica, Bambusa vulgaris, Caladium bicolor, Centrosema virginianum, Cnestis ferruginea, Culcasia scandens, Cyathula prostrata, Desmodium scorpiurus, Emilia sonchifolia, Heliconia psittacorum, Ipomea involucrata, Lagenaria sphaerica, Mimosa pudica, Nephrolepis bisserata, Panicum sp., Pentaclethra macrophylla, Plumeria rubra, Polyalthia longifolia, Pteridium aquilinum, Scoparia dulcis, Senna siamea, Sesamum radiatum and Sida acuta had the least frequency (33.33%). The vegetation of both sites indicated variation in composition of trees, shrubs, herbs, climbers and ferns. These heterogeneities may be a pointer to their varying adaptation levels and differential responses of plant species to pedological and anthropogenic influences.

Absheron Khagani Garden Study of Decorative Plants

The article describes the results of research on the study of the taxonomic composition of ornamental trees, shrubs and grasses consisting of 29 chapters, 41 genera, 46 species in the Khagani Garden of Absheron, forms of composition, rules of grouping plants in compositions, use of small architectural forms. It was determined that these plants are well adapted to the conditions of Absheron, are promising and can be widely used in the design of parks, gardens, alleys, in the creation of various compositions.

Herbivore–shrub interactions influence ecosystem respiration and biogenic volatile organic compound composition in the subarctic

Abstract. Arctic ecosystems are warming nearly 4 times faster than the global average, which is resulting in plant community shifts and subsequent changes in biogeochemical processes such as gaseous fluxes. Additionally, herbivores shape plant communities and thereby may alter the magnitude and composition of ecosystem respiration and biogenic volatile organic compound (BVOC) emissions. Here we determine the effect of large mammalian herbivores on ecosystem respiration and BVOC emissions in two southern and two northern sites in Swedish Scandes, encompassing mountain birch (LOMB) and shrub heath (LORI) communities in the south and low-herb meadow (RIGA) and shrub heath (RIRI) communities in the north. Herbivory significantly altered BVOC composition between sites and decreased ecosystem respiration at RIGA. The difference in graminoid cover was found to have a large effect on ecosystem respiration between sites as RIGA, with the highest cover, had 35 % higher emissions than the next highest-emitting site (LOMB). Additionally, LOMB had the highest emissions of terpenes, with the northern sites having significantly lower emissions. Differences between sites were primarily due to differences in exclosure effects and soil temperature and the prevalence of different shrub growth forms. Our results suggest that herbivory has a significant effect on trace gas fluxes in a productive meadow community and that differences between communities may be driven by differences in shrub composition.

Effects of clearcutting on species composition and community renewal of Rhododendron shrubs in northwest Guizhou Province, China

Tree base sprouting is the main reproduction and expansion mode of Rhododendron plants. By leveraging the plot survey method, the species composition, community renewal, and species diversity in three Rhododendron shrub communities in control, and before and after clearcutting (CK, D3yr, and D6yr, respectively) were studied. Moreover, the dissimilarity of Rhododendron communities in CK, D3yr and D6yr were analyzed. The results showed that there were 26 plant species belonging to 14 families and 22 genera, in 3 communities in total, with 19 species of shrub plants and 7 species of herbaceous plants. The number of species increased from 13 in CK to 23 in D3yr and then decreased to 20 in D6yr. The height and coverage of D3yr and D6yr reached 39.3% and 58.9% of that of CK, respectively. The relative height of CK, D3yr, and D6yr was 43.79%, 65.4%, and 58.54%, respectively. The coverage of D3yr and D6yr reached 60.8% and 114.70% of that of CK, respectively. The relative coverage of CK, D3yr, and D6yr was 19.05%, 83.24%, and 77.32%, respectively. The important value of Rhododendron plants in the communities increased from 0.42 in CK to 0.74 in D3yr, and then decreased to 0.67 in D6yr. The α diversity in the shrub layer of D3yr and D6yr were generally lower than those of CK except Pielou evenness index. The β diversity indicates that the similarity between CK and D3yr was lower, that between CK and D6yr was moderate, and that between D3yr and D6yr was higher. The sprouting height and coverage of Rhododendron plants was significantly correlated with age and sprouting time. The sprouting ability of Rhododendron plants increased first and then decreased with age, while the sprouting ability of Rhododendron plants with age of 10–12 years was the strongest. Clearcutting measures can improve the dominance of Rhododendron plants in the communities, promote the sprouting and renewal of Rhododendron population, and accelerate the succession rate of communities.

Changes in the species composition of the wood and shrubs vegetation due to anthropogenic impact in the Kuzminsk forest park

The article considers the structure, composition and condition of trees and shrubs in the eastern part of the forest park in Moscow region. It is shown that in the process of use and recreation, new species of plants are introduced in the territory, including those capable of natural distribution in these natural and climatic conditions. Due to biological characteristics, some species such as white maple or cerapadus are able to actively spread and replace local species.

Current Status and Taxonomical Composition of the Natural Dendroflora of the Hirkan National Park

The current state of the natural dendroflora of the Hirkan National Park was analyzed, an inventory of natural and cultivated plant species was carried out, the impact of climate change on biodiversity, the taxonomic composition of trees and shrubs, dominant species, and the distribution areas of the studied plants were comprehensively studied. In the forest ecosystem of Hirkan National Park, the area where the plants live change in several directions. In the deep layers of the forest, the sun hits a small amount. The level of illumination depends on the composition, age, density and geometric dimensions of the trees and shrubs that make up the forest. Depending on the amount of light, more or less shade-tolerant species grow in the lower tiers of the forest. HirkanNational Park has undergone anthropogenic impact in recent years. The forest usually consists of 2-3 tiers.

Prescribed Burning Effect on the Richness, Diversity and Forest Structure of an Endemic Reforested Pinus canariensis Stand (Canary Islands)

Forest fires are considered to play a fundamental role in structuring many forest plant communities. Prescribed burning is a useful tool to reduce fire risk by reducing the amount of fuel. Our main objective was to analyse the effects of prescribed burning on undergrowth species richness and diversity as well as on other characteristic variables in a reforested Pinus canariensis stand. In areas where prescribed burning had been performed in the last 10 years, we established 8 plots of 900 m2. Their respective control plots were in nearby unburned and environmentally similar areas. We systematically selected 10 points in each plot and sampled the presence, richness and diversity of species in 1 m2 grids. For each plot, the basal area, mean canopy height and average height of individuals were measured. In centred 10 × 10 m plots, shrub species were counted as well as the litter depth, litter cover and herb cover. There was no significant change in the number of species richness found when comparing burned vs. control plots. Additionally, we did not find any differences in diversity or shrub composition, nor were we able to determine the species associated with any of the treatments. The basal area and litter depth were the only parameters that revealed significant differences. Ecologically, prescribed fire is a good practice to reduce biomass accumulation in P. canariensis plantations, with little effect on species richness and forest structure but with positive effects for stand management, insofar as biomass reduction can help control summer wildfires.

Plant community attributes of a tropical dry forest physiognomically dominated by Heteroflorum sclerocarpum (Fabaceae)

Background: Heteroflorum (Fabaceae) is a monospecific genus endemic to western Mexico. Community attributes of the forest where H. sclerocarpum is found are scarcely known, as well as its similarity with other tropical seasonal forests.
 Question: What is the composition, structure, and diversity of the tropical deciduous forest where H. sclerocarpum is physiognomically dominant?
 Study site and date: The study was carried out in the buffer area of the Zicuirán-Infiernillo Biosphere Reserve, in the Churumuco municipality of Michoacán, Mexico (2014).
 Methods: In three 0.1-ha sites, we sampled trees with a diameter at breast height ≥ 1 cm and lianas whose rooted stem had a diameter of ≥ 1 cm. We calculated the density, biomass, rank-abundance, rank-basal area curves, and alpha and beta diversity measures for each site.
 Results: We recorded 64 species from 21 families in 0.3 ha. Fabaceae had the highest number of genera, species, individuals, and biomass in all sites sampled. The sites varied in richness (33-41 species), density (176-247 individuals), basal area (2-2.9 m2), and maximum height of trees (12-16 m). Rank-abundance curves differed significantly. Rarefaction curves showed that 0Dα and 1Dα did not differ among sites, while 2Dα separated one of the sites, which also showed a different diversity profile. Beta diversity did not show a strong species turnover among sites (0Dβ, 1.38-1.45; 2Dβ, 1.35-1.56).
 Conclusions: The composition of trees and shrubs in the forest sampled was similar to other seasonal forests, while the density and diversity were among the lowest values.

Characteristics and interactions of soil bacteria, phytocommunity and soil properties in rocky desertification ecosystems of Southwest China

Rocky desertification is a ubiquitous natural landscape in fragile karst areas, which has serious side effects on socioeconomic development and environmental protection. In order to explore in-depth the relationship between soil bacteria, plant communities and soil properties, species composition of herbs and shrubs was investigated, and soil properties were determined. Changes in soil bacterial community structure were detected by high-throughput sequencing of 16S rRNA V3-V4 regions. We found that the species compositions of herbs and shrubs was significantly different among the different rocky desertification grade. The soil bacterial phyla, Proteobacteria, Actinobacteria, Acidobacteria and Chloroflexi, were the most abundant species in the microbial community. Redundancy analysis showed that there were 5, 4, 3 and 3 kinds of soil bacterial phyla in the community and played a key role in the interactions between phytocommunity, soil properties and bacteria from the non-rocky desertification to the intense rocky desertification areas, respectively. The phytocommunity was significantly correlated with environmental factors (pH, Ca, soil enzymes and soil organic carbon). The relative abundance of Verrucomicrobium was low but was significantly correlated with soil properties. The MetaCyc pathway analysis found that the metabolic bacteria had the highest relative abundance in rocky desertification areas. The gradual reduction of the interactions of soil bacteria, plant community composition and multiple soil environmental factors resulted in the gradual degradation of rocky desertification. Our results provided a valuable scientific basis for understanding the interaction between soil bacteria, phytocommunity and soil properties in response to the evolution of rocky desertification, as well as highlighting the impact of microorganisms on different environmental factors.

Compositional attributes of invaded forests drive the diversity of insect functional groups

Forest canopies are important habitats for animal biodiversity globally. The structural and compositional components of canopies influence biodiversity, and recent advancements in remote sensing have given insight to these relationships. As invasive shrubs alter both the structure and composition of forests, we use handheld, mobile LiDAR to relate these elements and the overarching tree composition to insect biodiversity in Georgia, USA. Both LiDAR-derived structural metrics (vegetation density and Shannon vertical complexity index) were related to invasive shrub cover. We sampled four insect functional groups using two methods: woodboring beetles, mycophagous beetles, and bees were sampled using flight intercept traps 5 m aboveground, while litter-foraging ants were sifted from leaf-litter. From our generalized linear models, we found that tree composition strongly influenced all groups, though responses varied among functional groups. Woodboring beetles were negatively influenced more strongly by invasive shrub cover than vegetation density and also responded positively to tree and deadwood diversity. By contrast, bees and mycophagous beetles were unaffected by both the structure and composition of invasive shrubs, but were sensitive to tree composition. In the leaf-litter, ants were negatively influenced by invasive shrub cover and were sensitive to tree composition. Thus, the composition of forests is an important driver of insect diversity in our system, but with idiosyncratic responses among functional groups. Our results demonstrate the utility of LiDAR in clarifying the relationship between structure and composition on biodiversity in forest canopies, especially in regards to invasive plants.

Mechanisms and drivers of alternative shrubland states

AbstractGrassland‐to‐shrubland state change has been widespread in arid lands globally. Long‐term records at the Jornada Basin USDA‐LTER site in the North American Chihuahuan Desert document the time series of transition from grassland dominance in the 1850s to shrubland dominance in the 1990s. This broadscale change ostensibly resulted from livestock overgrazing in conjunction with periodic drought and represents the classic “grassland‐to‐shrubland” regime shift. However, finer‐scale observations reveal a more nuanced view of this state change that includes transitions from dominance by one shrub functional type to another (e.g., based on leaf habit [evergreen vs. deciduous], N2 fixation potential, and drought tolerance). We analyzed the Jornada Basin historic vegetation data using a fine‐scale grid and classified the dominant vegetation in the resulting 890 cells on each of four dates (1858, 1915, 1928, and 1998). This analysis allowed us to quantify on contrasting soil geomorphic units the rate and spatial distribution of: (1) state change from grasslands to shrublands across the Jornada Basin, (2) transitions between shrub functional groups, and (3) transitions from shrub‐to‐grass dominance. Results from our spatially explicit, decadal timescale perspective show that: (1) shrubland ecosystems developing on former grasslands were spatially and temporally more dynamic than has been generally presumed, (2) in some locations, shrublands initially developing on grasslands subsequently transitioned to ecosystems dominated by a different shrub functional type, with these changes in shrub composition likely involving changes in soil properties, and (3) some shrub‐dominated locations have reverted to grass dominance. Accordingly, traditional, broad characterizations of “grassland‐to‐shrubland” state change may be too simplistic. An accounting of these complexities and transitions from one shrub functional group to another is important for projecting state change consequences for ecosystem processes. Understanding the mechanisms, drivers, and influence of interactions between patterns and processes on transitions between shrub states defined by woody plant functional types will be germane to predicting future landscape change.

BIODIVERSITY OF FLORA AND FAUNA IN CHARYN NATIONAL PARK

The article discusses the biodiversity of the fauna, the vertebrate animals of the National park - fish, amphibians, reptiles, birds and mammals, as well as the assessment of the biodiversity of the most important component of the flora of protected areas - the species composition of trees and shrubs. According to the forest - growing and forestry zoning, the forest - growing province of the desert zone includes: saxaul and tugai forests, and in the Ili province of tugai forests, the forest-growing area of Ili ash, loch and willow tugai forests [1]. The flora of the national park includes more than 60 endemic, subendemic and rare species belonging to 20 families and 39 genera of plants [2,9]. Three species - the Ili ferula, the desert colossus and the kermek are relict, endemic. There are only 8 species that are narrowly endemic, of which three are acorn, ferula and sunbird - rare and listed in the Red Book of the Republic of Kazakhstan. There are 21 red Book species in total. Among them are barberry, ash, honeysuckle, turanga. Rare and endangered species listed in the Red Book of the Republic of Kazakhstan occupy a prominent place among the fauna [3,4,6]. According to the results of the assessment of the taxonomic biodiversity of the studied animals, relatively high indicators of representativeness were revealed for all their groups in the context of orders, families, genera and species. This also concerns the role of specially protected natural areas in the sustainable conservation of rare and endangered species listed in the Red Book of the Republic of Kazakhstan.

Diversity and composition of shrubs in Behali Reserve Forest of Biswanath district, Assam, with special emphasis on Gnetum gnemon L.

The study is focused to study the diversity and distribution of shrubs in the Behali Reserve Forest. A total of 46 species of shrubs belonging to 40 genera representing 25 families were documented. Rubiaceae and Lamiaceae were the dominant families. Pycnarrhena pleniflora has the highest IVI value of (48.25) followed by Coffea benghalensis (41.1). Plotting in Raunkiaer’s frequency class distribution it was found that the shrub community of BRF is heterogeneous in nature i.e. represents uniform species diversity which does not allow the dominance of a species. Among the recorded shrubs, Pycnarrhena pleniflora, Coffea benghalensis, Boeica filiformis, Gnetum gnemon and Dalhousiea bracteata has a good population status. Gnetum gnemon on the other hand a potential NTFP of BRF has an infrequent distribution which is due to its high economic value and unregulated collection. The market value of G.gnemon and its conservation needs are also presented.

Биоразнообразие лесных экосистем Баситчайского государственного природного заповедника

The study analyzed the natural plant species of the Basitchay State Nature Reserve, located in the south of the Lesser Caucasus (Zangelan District), the population status of plants in the areas, the taxonomic composition of trees, shrubs and grasses. To this end, the Ministry of Ecology and Natural Resources of the Republic of Azerbaijan and the Institute of Dendrology of Azerbaijan NAS got acquainted with the current situation in the district. During the monitoring, satellite images, GPS coordinates, etc. were used. Soil samples brought from the site were examined for 14 indicators of the mineral composition using Palintest equipment, soil sets 400. Quercus iberica grows in the forest cover of the mountainous part of the region and Carpinus caucasica, 2 types of junipers: Juniperus foetidissima, J. depressa Stev. and hybrid, there are Pistacia mutica, sorbus, mulberry, willow, poplar, hawthorn, foxglove, mountain xerophilous plants, shrubs, blackthorn, etc. Q. araxina, Celtis caucasica Willd., Carpinus orentalis, Pistacia mutica, Acer iberica grow on dry stony slopes, Ulmus araxina Takht. = U. minor Mill. Pyrus salicifolia forms woodlands with juniper. Such forests are characterized by xerophytic shrubs: Atraphaxis spinosa, Lonicera iberica, Cerasus microcarpa, Ephedra intermedia Schrenk. et. Camei, Rhamnus pallasii and Paliurus spina-christi. As a result, 27 species of trees, 18 shrubs and 11 species of herbs have been registered in the Basitchai State Nature Reserve. Of these species, 17 rare, endangered trees, 3 shrubs, 3 grass species, 6 trees and 2 shrubs of relict and endemic species have been identified.

The role of fluvial landforms as a driver of vegetation variation on a floodplain in southern Thailand

Floodplain vegetation is rare in southern Thailand due to the generally steep gradient through which major rivers flow and high pressure of land use. This study aims to increase the understanding of factors and processes that govern vegetation variation and diversity in a floodplain to provide information for conservation and management of this threatened and rare ecosystem. A total of 20 plots, each 625 m2, were laid on three broad categories of fluvial landforms to collect data on the number of tree species (woody plants with diameter at breast height (DBH) ≥ 5 cm), soil variables, flooding, history of land use and distance to the inner curve of the channel in Nong thung thong Non-Hunting Area, Thailand. Three 4 m2 subplots were nested within each 625 m2 plot to estimate shrub composition and coverage. The alpha and beta diversity of the tree species in each fluvial landform were calculated. The relationships between vegetation data and environmental factors were explored through transformation-based Redundancy Analysis (tb-RDA) and univariate analyses. Beta diversity between abandoned channel and ridge plots, and between ridge and shallow depression plots was higher than the dissimilarities within each fluvial landform, and the balanced variation in abundance contributed to the major part of the dissimilarities. These results indicate different tolerance ranges or competitive ability of species between these fluvial landforms. Results from the tb-RDA showed that tree species composition varied with fluvial landforms and soil calcium content. Median of flooding was associated with fluvial landforms. In addition, soil calcium content could be controlled by fluvial landform because clay and calcium were correlated, and both were associated with fluvial landforms. These results suggest that variation in fluvial landforms causes variation in flooding duration, edaphic factors, vegetation variation, and ultimately, the biodiversity in this floodplain.